Photo-rechargeable zinc ion capacitors using MoS2/NaTaO3/CF dual-acting electrodes prepared by photodeposition method

Abstract

This study presents an innovative approach to integrated energy systems by combining solar energy harvesting and electrochemical charge storage in a single modular platform. By strategically incorporating a MoS₂/NaTaO₃ heterostructure material, we have developed a photo-rechargeable zinc-ion capacitor (PR-ZIC) that utilises the synergistic benefits of this unique configuration. The photoactive MoS₂/NaTaO₃ cathode effectively absorbs light and charges the capacitor, enabling continuous light-driven operation. Experimental studies show that the MoS₂/NaTaO₃-based photo-rechargeable zinc-ion capacitor (PR-ZIC) exhibits a significant increase in capacitance when irradiated with light, with a 2.76-fold increase (93.94 mF cm⁻²) compared to dark conditions (33.95 mF cm⁻²) at a 10 mV s⁻¹ scan rate. In addition, these capacitors show a photocharge voltage response of about 860 mV and excellent cyclability, retaining about 96% of their capacity over 4000 charge–discharge cycles. The results of this study highlight the potential of the MoS₂/NaTaO₃ heterostructure as a high-performance photoactive material for advanced photo-rechargeable zinc-ion energy storage devices. This integrated approach offers innovative off-grid energy solutions by optimizing device footprint, minimizing energy transfer losses and providing sustainable energy storage options.